SYDNEY, July 20 (Xinhua) -- Australian researchers on Friday said they have identified crucial features of human chromosomes, pointing to a better understanding and treatment of chronic conditions ranging from cancer to heart disease.
Their study involves telomeres, the DNA segments at the end of chromosomes that shorten in length with age. The shortening signals aging cells to stop dividing and normally acts as an important barrier to cancer growth. But the length of telomeres is also a crucial disease marker, and people born with abnormally short telomeres can suffer from high rates of cancer and other illnesses.
The researchers' latest findings involved identifying the underlying cause that changes the loop-like features of telomeres as people age.
"Telomeres normally form a loop structure, where the chromosome end is hidden. We found that when the telomere-loop unfolds, the chromosome end is exposed and the cell perceives this as broken DNA," said Dr Tony Cesare from the Children's Medical Research Institute in a statement.
"We knew that telomeres regulate cellular ageing, but our new data explain the trigger that makes telomeres unhealthy," said Cesare, who led the study that also involved collaboration with scientists from the University of New South Wales. Their work used advanced super-resolution microscopes to observe the telomere-loops.
The researchers found that the telomeres could be "opening up" in young people, leading to disease, while the structures could also change in response to chemotherapy drugs.
Analyzing and managing the structure and behavior of the telomeres and their loop-like features could point to better ways of preventing and treating major diseases, according to the study published in the Molecular Cell scientific journal.
"We've shown that it's not just telomere length, but telomere structure and telomere health that we need to understand," said Cesare.
